Azo dyestuffs



Patented Feb. 28, 1939 PATENT OFFICE AZO DYESTUFFS Hans Boos, Leverkusen-I. G. Werk, Germany, as-

signor to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application November 7, 1935, Se-

rial No. 48,775. In Germany November 30,

5 Claims.

The present invention relates to new azo dyestuffs, more particularly it relates to azo dyestufis which may be represented by the probable general formula wherein R stands for the radical of a diazo compound. suitable for preparing azo dyestuifs with the inclusion of a diazo azo compound, R, stands for a radical of the benzene series, and R" stands for a radical of a nondiazotizable yellow component of the group consisting of 1-aryl-5- pyrazolone-3-carboxylic acids and ortho-hydroxy carboxylic acids of the benzene series.

My new dyestuffs are obtainable by coupling any diazo compound or diazo azo compound with a 2 aminobenzoylamino 5-naphthol-7-sulfonic acid, further diazotizing and coupling with a 1- aryl-5-pyrazolone 3-carboXylic acid or an orthohydroxy carboxylic acid of the benzene series, which yellow components may bear in the aryl nucleus substituents, such as halogen, alkyl, the carboxylic acid group, the sulfonic acid group, there being excluded, however, the amino group.

My new dyestuffs are, in form of their alkali metal salts, generally red to brown powders, dyeing the vegetable fiber generally bluish red to brown shades, which can be discharged to a pure Hols white both in a neutral as well as in an alkaline diazotized in the known manner and coupled with a solution alkaline with sodium carbonate of 36.5 parts by Weight of 2-meta-amino-benzoylamino-5-naphthol-7-sulfonic acid. The dyestufi formed is filtered 01f with suction, stirred into a paste as finely as possible, and diazotized, at room temperature, by stirring for an hour with nitrite and hydrochloric acid. Then the diazotization mixture is stirred into a solution alkaline with sodium carbonate of 20.5 parts by weight of 1- phenyl-5-pyrazolone-3-carboxylic acid. The coupling is soon complete, andthe dyestufi is isolated in the known manner. It dyes cotton very clear orange shades, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

The dyestufi obtained in this manner corresponds to the following formula:

COOH

Earample 2.--10.'7 parts by weight of orthotolui-dine are. diazotized in the known manner and coupled with a solution alkaline with sodium carbonate of 36.5 parts by weight of Z-para-aminobenzoylamino-5-naphthol7-sulfonic acid. For the rest, the procedure is the same as described in Example 1, and a dyestuff dyeing somewhat more reddish shades than the dyestuff of EX- ample 1, but exerting otherwise similar properties is obtained, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

The dyestuff obtained in this manner corre-- sponds to the following formula:

Example 3.2'7.'7 parts by weight of 4-aminoazobenzene-l-sulfonic acid are diazotized and coupled, in a solution acid with acetic acid, in the known manner, with 36.5 parts by weight of 2 para-aminobenzoylamino 5-,naphthol-7-Jsulfonic acid. By suspending with water, the dyestuff purified by previous isolation is finely dispersed and diazotized with an excess of nitrite H a S NH:

and hydrochloric acid. Then it is coupled, in a solution alkaline with sodium carbonate, with 22 parts by weight of l-phenyl--pyrazolone-3-carboxylic acid. The dyestufr" obtained dyes the vegetable fiber bluish red shades, which are dischargeable to a pure white both in a neutral as well as in an alkaline reacting medium.

The dyestuif obtained in this manner corresponds to the following formula:

H 0 as When substituting the aminoazobenzene monosulfonic acid by an equivalent quantity of the amino azodyestufi from diazotized 2-naphthylamino-4,8-disulfonic acid and meta-toluidine and working otherwise according to the directions given in paragraph 1 of the example, there is obtained a dyestufi yielding somewhat more bluish shades, which also can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

Example 4.--13.6 parts by weight of diazotized monoformylmetaphenylene diamine are coupled, as indicated in Example 1, with 36.5 parts by weight of Z-para-aminobenzoylanino-5-naphthol-Y-sulfonic acid and finally, likewise as indicated in Example 1, with 20.5 parts by weight of the methyl ester of 1-phenyl-5-pyrazolone-3- carboxylic acid. After having been isolated, the dyestufi is boiled for hour in a suspension of sulfuric acid of 5% strength. Thus a dyestufi is obtained which dyes cotton scarlet red shades and which can be developed on the fiber in the known manner with beta-naphthol to a well dischargeable scarlet which is fast to washing. By

developing with diazotized bases, such as for instance para-nitraniline and similar ones, reddish brown shades are obtained, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

The dyestuif obtained in this manner corresponds to the following formula:

COOH

Example 5.9.3 parts by weight of aniline are diazotized in the known manner and coupled with 36.5 parts by weight of Z-(para-aminobenzoylamino) -5-naphthol-7-sulfonic acid. The dyestuff formed is filtered with suction and, after pasting, further diazotized, while stirring for several hours with nitrite and hydrochloric acid. This diazotization mixture is added to a concentrated aqueous solution of 14 parts by weight of COOH salicylic acid, to which 20 parts by weight of an aqueous solution of caustic soda have been added. Coupling is complete rather quickly, and the dyestufi of the formula COOH is isolated in the known manner; it dyes cotton a yellowish red of good dischargeability both in a neutral as well as in an alkaline reacting medium.

When using in. this example ortho-toluidine, ortho-anisidine or other bases of this kind, more bluish red dyestuffs of similar properties are obtained.

Example 6.-13.6 parts by weight of metaaminoformanilide are diazotized in the usual manner with nitrite and hydrochloric acid. For the rest, the procedure is the same as described in Example 5 using, however, for the final coupling 15.5 parts by weight of ortho-cresotinic acid. After isolation the dyestufi is suspended in sulfuric acid of 5% strength and heated at boiling temperature for about hour. The dyestufi obtained in this manner, of the formula COOH can be diazotized and developed on the fiber in the known manner with diazotized para-nitraniline. In the latter case a brown of good dischargeability both in a neutral as well as in an alkaline reacting medium is obtained.

I claim: 1. Dyestuffs of the general formula R--N=N NHCOR-N=N-R" HOIS wherein R stands for a member selected from the group consisting of radicals having 1 or 2 benzene nuclei and azo compounds thereof, R stands for a benzene nucleus, and R" stands for a radical of a 1-aryl-fi-pyrazolone-3-carboxylic acid,

dyeing the vegetable fiber generally bluish red to brown shades, which can be discharged to a pure white both in a neutral aswell as in an alkaline reacting medium.

HOIS

2. Dyestuffs of the general formula RN=N wherein R. and R. stand for benzene nuclei, and

R" stands for a radical of 1-aryl-5-pyrazolone- 3-carboxylic acid, dyeing the vegetable fiber generally bluish red to brown shades, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

3. The dyestufi having in its free state the following formula:

dyeing the vegetable fiber clear orange shades,

, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

4. The dyestuff having in its free state the following formula:

OOOH

dyeing the vegetable fiber clear reddish orange shades, which can be discharged to a pure white both in a neutral as well as in an alkaline reacting medium.

5. The dyestuffs having in their free state the following formula:

OOOH 

